Field of the Invention
The invention refers to a switching arrangement for the hydraulic drive means of a full-track vehicle, in which arrangement at least one drive motor is associated with each respective endless, ground-engaging track at both sides of the longitudinal axis of the vehicle.
Description of the Prior Art
The track chassis of full-track vehicles allow a vehicle of this type to travel along a straigth path, but also along a curved path. For the purpose of travelling along a curved path, one of both endless, ground-engaging track at one side of the longitudinal axis of the vehicle can, in a manner known per se, be blocked or be driven in an opposite direction to the track or tracks on the other side for the purpose of turning the vehicle on a narrow place. When travelling along a straight path, the drive motors of the tracks on both sides of the longitudinal axis of the vehicle are driven in the same sense. Chassis with endless, ground-engaging tracks at both sides are primarily uses, in the mining industry, for drift-advancing machines and exploiting machines, but also for movable consolidating trestles and, in particular, in connection with supporting props used for securing the excavating edge. When travelling along a curved path and, in particular, when turning the vehicle in a narrow space, there are required high driving torques, and known constructions are designed such that a separate pump for the pressurized fluid and a separate switching arrangement are provided for each hydraulic motor. This respective separate energizing equipment must be designed in accordance with the required maximum driving power of the respective pump. The dimensioning of such driving units results, as a rule, in a compromise between the achievable travelling speed for travelling along a straight path and the required torque or, respectively, high traction force of the tracks for travelling along a curved path or for turning the vehicle around.